There are hundreds of varieties of drum gear couplings, but the basic forms are two:

　　1. Combination of internal and external teeth;

　　2. End-tooth combination type.The other forms are all deformations on these two foundations.The gear clutch with internal and external gears transmits a relatively large torque. The design takes into account the different needs of users and is deliberately designed so that the lengths of the shaft ends on both sides of the teeth are not consistent, so that users can choose the installation direction according to their needs.Therefore, it does not specify which end faces where.

　　Pay attention to when installing:

　　1. If it is replaced on the original equipment, it should generally be in the same direction as the original one. If it is a newly designed and manufactured equipment, then the more internal and external tooth joint surfaces should be pressed without interference with other surrounding parts. The more reliable the installation principle.

　　The maintenance of drum gear couplings is generally carried out as follows:

　　1. Check the gear tooth surface meshing of the coupling. The contact area is not less than 50 along the tooth height and not less than 70 along the tooth width. The tooth surface must not have serious pitting, wear and cracks.

　　2. The full circle runout of the outer gear ring of the coupling is not more than 0.03mm, and the end circle runout is not more than 0.02mm.

　　3. If it is necessary to remove the gear ring, use special tools and do not knock, so as not to bend or damage the shaft.When reinstalling, heat the ring gear to about 200°C before installing it on the shaft.The interference between the outer gear ring and the shaft is generally 0.01~0.03mm.

　　4. When reinstalling the intermediate tube or other parts, it should be assembled according to the original markings and data.

　　5. Tighten the bolts evenly with a torque wrench.